Tsunetaka was back in the alley before dawn, his sword cutting through the air with disciplined precision.
At Level 3 Sword Mastery, his movements were no longer clumsy; they were fluid and sharp. Every swing was calculated, his breath perfectly synchronized with his strikes. He wasn't just practicing anymore—he was conditioning muscle memory.
Around mid-morning, the System screen flickered.
**[SYSTEM UPDATE: SWORD MASTERY - LEVEL 3 (280/300 COMPLETE)]**
**[PROGRESS NOTICE: 20 POINTS UNTIL LEVEL UP]**
His muscles burned, but he pushed through. The sword felt lighter today, almost like an extension of his arm.
**[SYSTEM UPDATE: SWORD MASTERY - LEVEL 4 REACHED]**
**[NEW FORMS UNLOCKED: 12 NEW SUN BREATHING STYLES ADDED]**
**[DEMON SLAYER MARK: ACTIVATED]**
**[TRANSPARENT WORLD - LEVEL 4 REACHED]**
A violent tremor ripped through Tsunetaka's body, forcing him to drop the practice sword and clutch his chest. It felt like his blood was boiling, his veins rewriting themselves under his skin. A sharp, burning pain erupted across his forehead—the Mark manifesting.
But instead of overwhelming him, the System forcibly rewired his biology. He felt the "curse"
The boiling sensation in his veins cooled, settling into a steady, rhythmic hum. The System wasn't just giving him the power; it was fundamentally rewriting his biology to sustain it. The fatal curse that claimed every Demon Slayer at twenty-five was being neutralized, converted into a permanent source of vitality rather than a ticking clock.
He touched his forehead.He checked his techniques next.
**[SYSTEM MENU - TECHNIQUES]**
**[DEMON SLAYER MARK: ACTIVE (PERMANENT) - Biological Immortality Achieved]**
**[TRANSPARENT WORLD: LEVEL 4 (Absolute Perception)]**
**[TOTAL FORMS: 12 SUN BREATHING TECHNIQUES]**
*Form 1: Solar Heat Haze*
*Form 2: Rising Sun Slash*
*Form 3: Ray of Sunlight Sky Turn*
*Form 4: Sunflower Thrust*
*Form 5: Twilight Radiance*
*Form 6: Setting Sun Stance*
*Form 7: Bright Moon Slash*
*Form 8: Falling Sun*
*Form 9: Solar Eclipse*
*Form 10: Full Solar Revelation*
*Form 11: Dawn's Ascent*
*Form 12: Midday Radiance*
**[INNATE ADAPTABILITY: +100% TRAINING EFFICIENCY]**
**[CURSE CONVERSION: 100% - FATALITY AVOIDED, POWER PERMANENT]**
**
The moment his fingers closed around the hilt, something changed. The sword felt different—warmer, almost alive. His grip was perfect, his stance natural. Level 4 Transparent World pulsed beneath his skin, granting him a level of perception that bordered on godlike.
He swung once.
The blade cut through the air with a sound like a dying sun.
He raised a hand to his temple, activating **[Transparent World - Level 4]**. The world instantly dissolved into wireframes and skeletal structures. Walls became mere outlines, floors vanished, and everything hidden beneath became visible. He scanned the city blocks.
*There.*
Three streets over, lurking inside the abandoned commercial center—a Tiger-level monster prowling the shadows. Without hesitation, he moved.
He vanished. The air cracked with a deafening boom as he instantly broke the sound barrier, his movements a blur to anyone watching. Using the Demon Slayer Mark's enhanced speed, he crossed three city blocks in a fraction of a second.
The Tiger-level monster inside the warehouse barely had time to twitch its head before Tsunetaka was standing directly behind it.
His grip shifted, the blade singing as he unleashed **[Form 3: Ray of Sunlight Sky Turn]**.
The sword moved in a seamless, whirling arc—a blinding wheel of solar fire that carved through the concrete and steel behind the monster. The Tiger-level creature didn't even hear the warning shot before the burning edge connected, severing both arms clean off its mutated body.
The monster howled in agony, stumbling backwards as molten flesh cauterized instantly. It was fast—too fast for a normal human—lunging with its remaining claws at his neck.
Tsunetaka didn't flinch. Transparent World mapped every muscle contraction, predicting the trajectory perfectly. He stepped aside by mere millimeters, the claws whistling past his ear.
The monster roared, more enraged than ever, throwing its weight against the walls to crush him.
Tsunetaka's eyes tracked the movements without effort—every muscle fiber, every blood vessel, every nerve pathway was visible to him through the translucent world. Level 4 was a glimpse; Level 5 was something far greater.
Before the creature could react, Tsunetaka moved. It wasn't a slash—it was a precise thrust, his blade guided by the infallible perception of Transparent World. The sword entered the monster's throat at an impossible angle, piercing through its spine and out the back of its skull.
He reappeared in his apartment as suddenly as he left, the monster's blood already washed off his blade. The System hummed softly, processing data from the battle. His training efficiency had increased—Level 4 Transparent World was adapting to his combat style, making future battles even easier to predict and counter.